1. Field of the Invention
The present invention relates to an apparatus for and a method of processing a substrate such as a semiconductor wafer of the like at a time, and more particularly to an apparatus for and a method of processing a substrate by successively processing the substrate with a chemical liquid, cleaning the processed substrate with pure water or the like, and spin-drying the cleaned substrate.
2. Description of the Related Art
Heretofore, it has been customary to process a substrate by successively processing the substrate with a chemical liquid, cleaning the processed substrate with pure water or the like, and spin-drying the cleaned substrate with an apparatus which treats the substrate with the chemical liquid and cleans the processed substrate, and another separate apparatus which spin-dries the cleaned substrate. The separate apparatus have been used because if the successive processing steps are performed by one apparatus, then a substrate processing liquid such as a chemical liquid tends to be splashed back onto the substrate or turned into a mist which adversely affects a film on or a processed surface of the substrate when the substrate is spin-dried.
Specifically, the substrate is liable to be contaminated by a substrate processing liquid which is splashed back after it is expelled from the substrate or a substrate holder that holds the substrate, a substrate processing liquid which is splashed back from collision with the substrate processing liquid that has been deposited on the inner wall surface of a scattering prevention cup after it is expelled from the substrate or the substrate holder that holds the substrate, and a substrate processing liquid mist that is produced when the substrate processing liquid referred to above is splashed back. While the substrate is being spin-dried, in particular, the surface of the substrate is exposed and easily susceptible to the splashed-back substrate processing liquid, the mist, etc.
The conventional practice to use the separate apparatus for processing the substrate with the chemical liquid and cleaning the processed substrate with pure water or the like, and spin-drying the cleaned substrate has been disadvantageous in that the substrate being processed tends to suffer increased footprints, and the need for transferring the substrate between the apparatuses results in a reduction in the throughput. For this reason, there has been a demand for a single apparatus that is capable of successively processing a substrate through various steps including spin-drying the substrate.